Baculovirus (Autographa californica) has been used for the expression of foreign proteins (Luckow et al, 1988, Biotech. 6:47-55; Luckow et al, 1989 Virol. 170: 31-39). However, a consistent level of foreign gene expression approaching that of the native polyhedrin has not been achieved by heretofore constructed baculovirus systems.